The Keepers' Tattoo by Gill Arbuthnott
Nyssa is shocked when she is forced to leave the tavern where she works because the Shadowmen are hunting her. Marius, her uncle, tells her that she has a secret tattoo on the back of her head that contains secret information. Alaric, the leader of the Shadowmen, wants the information for himself. As Nyssa hides from them, she discovers secrets about her past that she never imagined.
She is a member of the Keepers clan and has a twin brother who is thought to be dead. Nyssa must stop Alaric from finding the information, or he may be able to conquer all of the islands.